Rf architecture utilizing a mimo chipset for near field proximity sensing and communication

ABSTRACT

A re-configurable RF architecture includes both a 2×2 MIMO mode and a 1×2 MIMO mode. The 2×2 MIMO mode includes a first RF chain coupled with a first dual band antenna and configured to both transmit (Tx) and receive (Rx) using two different RF protocols. The 2×2 MIMO mode also includes a second RF chain coupled with a second dual band antenna and configured to both Tx and Rx using a single RF protocol. The first RF chain may be coupled with a third antenna configured for near field proximity sensing. The RF architecture is reversibly switchable from the 2×2 MIMO mode to the 1×2 MIMO mode when near field proximity detection is required. In the 1×2 MIMO mode the Tx/Rx capabilities of the second chain using the second dual band antenna are retained and the first chain is configured for Rx only capability using the third antenna.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 13/957,337, filed on Aug. 1, 2013, having Attorney Docket No.ALI-233, and entitled, “RF Architecture Utilizing a Mimo Chipset forNear Field Proximity Sensing and Communication,” U.S. patent applicationSer. No. 13/957,337 is related to the following applications: U.S.patent application Ser. No. 13/952,532, filed on Jul. 26, 2013, havingAttorney Docket No. ALI-232, and entitled “Radio Signal Pickup From AnElectrically Conductive Substrate Utilizing Passive Slits,” U.S. patentapplication Ser. No. 13/919,307, filed on Jun. 17, 2013, having AttorneyDocket No. ALI-206, and entitled “Determining Proximity For DevicesInteracting With Media Devices,” and U.S. patent application Ser. No.13/802,646, filed on Mar. 13, 2013, having Attorney Docket No. ALI-230,and entitled “Proximity-Based Control Of Media Devices For MediaPresentations,” all of which are hereby incorporated by reference intheir entirety for all purposes.

FIELD

These present application relates generally to the field of personalelectronics, portable electronics, media presentation devices, audiosystems, and more specifically to a RF architecture that is reversiblyswitchable between a 2×2 MIMO mode and a 1×2 MIMO mode while maintainingdual band RF communications in either mode and receive only near fieldproximity detection in the 1×2 MIMO mode.

BACKGROUND

MIMO is an abbreviation for Multiple-Input Multiple Output RF devicesthat have the ability to simultaneously handle multiple RF data inputsand multiple RF data outputs. RF devices that include MIMO capabilitymay use a RF antenna to send and receive more than one communicationsignal simultaneously. For example, transmitting a WiFi signal using adual band antenna and receiving a Bluetooth (BT) signal using the samedual band antenna. A 2×2 MIMO architecture may provide two RF paths thatuse two RF chains with each chain configured for receiving andtransmitting a RF signal. A 1×1 MIMO architecture, also called SISO,allows for one RF path with a single RF chain that is capable oftransmitting or receiving a RF signal. MIMO systems that use multiple RFantennas can take advantage of multipath effects that result in improvedrange and capacity due to more reliable signal quality and increasedbandwidth.

The MIMO architectures may utilize one or more antennas or a dual bandantenna to transmit and receive RF signals. Those antennas are typicallyoptimized for the intended RF bands the MIMO will be in communicationswith, such as WiFi (2.4 GHz, 5 GHz) and Bluetooth, for example. However,some systems that incorporate a MIMO architecture may include featuresthat requires an antenna optimized for another function, such as nearfield proximity detection. In some applications, the antenna to be usedfor near field proximity detection may be subject to design constraintssuch as imposed by industrial design considerations (e.g., estheticrequirements), chassis/enclosure design, just to name a few. In otherapplications, the antenna to be used for near field proximity detectionmay be configured to not be optimized for any of the frequency bandsused by the MIMO. For example, it may be desirable to have anintentionally detuned antenna for antenna for near field proximitydetection because it will be less sensitive to signal strength (e.g.,RSSI) generated by transmitting devices in the far field region(e.g., >0.5 meters from the antenna) and more sensitive to transmittingdevices that are in the near field or very near field (e.g., <0.5 metersfrom the antenna) or are in direct contact with the antenna. Thereforean antenna that is detuned and/or not optimized for RF bands such asthose used for WiFi or Bluetooth, may be desirable for some applicationsthat also include a MIMO architecture.

Thus, there is a need for a RF architecture that takes advantage of MIMOwhile also incorporating antennas optimized for near field proximitydetection into the MIMO architecture while maintaining the advantages ofthe MIMO architecture.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments or examples (“examples”) of the present applicationare disclosed in the following detailed description and the accompanyingdrawings. The drawings are not necessarily to scale:

FIG. 1A depicts a block diagram of one example of a RF frontendarchitecture, according to an embodiment of the present application;

FIG. 1B depicts a block diagram of the RF frontend architecture of FIG.1A when set to a 2×2 MIMO mode, according to an embodiment of thepresent application;

FIG. 1C depicts a block diagram of the RF frontend architecture of FIG.1A when set to a 1×2 MIMO mode, according to an embodiment of thepresent application;

FIG. 1D depicts a more detailed block diagram of one example of a RFfrontend architecture, according to an embodiment of the presentapplication;

FIG. 1E depicts a block diagram of the RF frontend architecture of FIG.1D when set to a 2×2 MIMO mode, according to an embodiment of thepresent application;

FIG. 1F depicts a block diagram of the RF frontend architecture of FIG.1D when set to a 1×2 MIMO mode, according to an embodiment of thepresent application;

FIG. 2 depicts an exemplary computer system according to an embodimentof the present application;

FIG. 3 depicts a flow diagram of one example of a method formulti-channel dual band wireless communication and wireless near fieldproximity detection, according to an embodiment of the presentapplication;

FIG. 4A depicts a top plan view of one example of an antenna and passiveslits formed in a substrate of an electrically conductive material,according to an embodiment of the present application;

FIG. 4B depicts a cross-sectional view along line AA-AA of FIG. 4A of anantenna and passive slits formed in a substrate of an electricallyconductive material, according to an embodiment of the presentapplication;

FIG. 4C depicts an example schematic diagram of electrical connectionswith the antenna, according to an embodiment of the present application;and

FIGS. 4D-4E depict examples of a live device generating a RF signal thatmay be detected by a system using an antenna and passive slits,according to an embodiment of the present application.

DETAILED DESCRIPTION

Various embodiments or examples may be implemented in numerous ways,including as a system, a process, an apparatus, a user interface, or aseries of program instructions on a non-transitory computer readablemedium such as a computer readable storage medium or a computer networkwhere the program instructions are sent over optical, electronic, orwireless communication links. In general, operations of disclosedprocesses may be performed in an arbitrary order, unless otherwiseprovided in the claims.

A detailed description of one or more examples is provided below alongwith accompanying drawing FIGS. The detailed description is provided inconnection with such examples, but is not limited to any particularexample. The scope is limited only by the claims and numerousalternatives, modifications, and equivalents are encompassed. Numerousspecific details are set forth in the following description in order toprovide a thorough understanding. These details are provided for thepurpose of example and the described techniques may be practicedaccording to the claims without some or all of these specific details.For clarity, technical material that is known in the technical fieldsrelated to the examples has not been described in detail to avoidunnecessarily obscuring the description.

FIG. 1A depicts a block diagram 100 a of one example of a RF frontendarchitecture 100 (RF 100 hereinafter). Unless otherwise stated, elementsin RF 100 may be implemented using a variety of technologies includingbut not limited to an integrated circuit (IC), a mixed-signal IC, anapplication specific integrated circuit (ASIC), a mixed signal ASIC,discrete electronic components, combinations of discrete electroniccomponents and IC's or ASIC's, just to name a few. RF 100 includes RFcircuitry 150 having circuitry for a 2×2 Multiple-Input Multiple-Output(MIMO) and a 1×2 MIMO. One or more signals (e.g., 157, 155), eitherinternal to RF 100, external to RF 100, or both may be used to set a 2×2MIMO mode or 1×2 MIMO mode. For example, a mode signal 155 received byRF circuitry 150 may be used to determine with of the two MIMO modes isset. As one example, if the mode signal 155 is active high, then the 2×2MIMO mode is set, and if the mode signal 155 is active low, then the 1×2MIMO mode is set. In other examples, another signal or group of signalsmay set the MIMO mode or cause the mode signal 155 to be set to one ofthe two MIMO modes. For example, one or more signals on port 157 of RFcircuitry 150 may be used to set the MIMO state or cause the mode signal155 to be set to a particular value or voltage level (e.g., logic 1 orlogic 0).

RF circuitry 150 may include two separate RF chains and their associatedcircuitry and antennas. For purposes of explanation, a dashed line 143will be used to visually demark a first RF chain 151 from a second RFchain 152 so that the functionality of the two RF chains may bedescribed with clarity. In the first RF chain 151, circuitry 129 may beelectrically coupled (125, 127) with RF circuitry 150 and a RF switch160. Connections 125 and 127 may be for ports on RF circuitry 150 thatsupport different RF bands such as 2.4 GHz, 5 GHz, and Bluetooth (BT),for example. Connections 125 and 127 may also be used to couple RFsignals such as those associated with antenna 130 as will be describedbelow. RF chain 151 may include two antennas such as antenna 120 andantenna 130, both of which are electrically coupled (126, 136) with RFswitch 160. RF switch 160 may select between antennas 120 and 130 basedon a signal 153 received by the switch 160 from RF circuitry 150.Antenna 120 may be a dual band antenna or a dual band chip antenna. Thedual band chip antenna may be monolithically integrated with asemiconductor die that include some or all of the circuitry in RF 100and/or RF circuitry 150. The dual band chip antenna may be positioned(e.g., floor planned) at a specific location on the die such as at acorner or a side of the die. There may be multiple dual band chipantennas and those antennas may be positioned at opposing corners of thedie or at opposing sides or edges, for example. Antenna 130 may be anantenna specifically configured for near field detection of externalsources of RF signals. For example, antenna 130 may be a near fieldproximity detection antenna configured to generate a RF signal when atransmitting RF device is placed directly on or in contact with antenna130, or positioned in near field proximity or very close near fieldproximity of antenna 130. Very close near field proximity may comprise adistance from the antenna 130 that is approximately 0.5 meters or less.More preferably, 50 mm or less. Even more preferably, 30 mm or less.Near field proximity may comprise a distance that is greater than 0.5meters. The foregoing are non-limiting examples of what may define nearfield proximity or very close near field proximity and actual valueswill be application dependent. Antenna 130 may be configured to beintentionally detuned (e.g., to a lower frequency) from a targetfrequency, such as the frequency or frequencies of the external sourcesof RF signals and/or one or more of the dual band frequencies of RF 100.For example, if the target frequency is 2.4 GHz, then antenna 130 may bedetuned to a lower frequency that may be approximately in a range fromabout 0.5 GHz to about 1.0 GHz. Antenna 130 will be described in greaterdetail below. Examples of target frequencies include but are not limitedto: 2.4 GHz; 2.4 GHz-2.48 GHz; from about 2.4 GHz to about 2.48 GHz; 5GHz; unlicensed bands, licensed bands, cellular bands, bands used by 2G,3G, 4G, and 5G devices, Bluetooth bands, any of the 802.11 bands,military bands, just to name a few. Antenna 130 may be tuned to thetarget frequency or in some examples may be detuned to a frequency rangethat is below that (i.e., lower) of the target frequency or to afrequency range that is above (i.e., greater) that of the targetfrequency.

RF chain 152 includes circuitry 119 that may be electrically coupled(115, 117) with RF circuitry 150. Connections 115 and 117 may be forports on RF circuitry 150 that support different RF bands such as 2.4GHz, 5 GHz, and Bluetooth (BT), for example. RF chain 152 may include anantenna 110 that may be a dual band antenna or a dual band chip antennaas described above for antenna 120. RF circuitry 150 may supportmultiple MIMO modes, such as a 2×2 MIMO mode and a 1×2 MIMO mode and RFcircuitry 150 may reversibly switch between the multiple MIMO modes,such as between 2×2 MIMO and 1×2 MIMO modes (e.g., in response to signal155 and/or 157). When the 2×2 MIMO mode is set, RF circuitry 150 isconfigured for dual band RF communication for both transmit (Tx) andreceive (Rx) using both antennas (110, 120). Moreover, the dual band RFcommunications may occur simultaneously such that RF chain 151 may useits antenna 120 to Tx/Rx on dual RF bands, such as WiFi 2.4 GHz and/orWiFi 5 GHz or Bluetooth and/or WiFi 5 GHz. Similarly, RF chain 152 mayuse its antenna 110 to Tx/Rx on dual RF bands, such as WiFi 2.4 GHzand/or WiFi 5 GHz or Bluetooth and/or WiFi 5 GHz. RF circuitry 150 maybe configured so both of the RF chains (151, 152) may Tx/Rx usingBluetooth, or only one of the RF chains (151, 152) may Tx/Rx usingBluetooth (e.g., BT on RF chain 152 only). Ports 115, 117, 125, and 127may be configured for different frequency bands. For example, ports 115and 125 may be assigned for a RF band such as 2.4 GHz, and ports 117 and127 may be assigned to another RF band such as 5 GHz. In someapplications, all of the ports (115, 117, 125, and 127) may besimultaneously Tx/Rx RF signals over their respective RF bands and inother application some or all of the ports (115, 117, 125, and 127) maybe idle. Actual port traffic may be determined by a system or devicethat incorporates RF 100.

2×2 MIMO Mode

In FIGS. 1A and 1B, for purposes of explanation, assume mode signal 155is set to the 2×2 MIMO mode. In the 2×2 MIMO mode, RF switch 160electrically couples 161 the antenna 120 with circuitry 129 and dualbandwidth RF communication using antenna 120 is enabled such that dualRF bands denoted as B1 and B2 may both simultaneously Tx 122 and Rx 124RF signals via electrical coupling 128 between circuitry 129 and antenna120. Here B1 may be associated with port 125 and B2 with port 127. Whilein the 2×2 MIMO mode, antenna 130 is electrically decoupled fromcircuitry 129 by switch 160. Antenna 130 may be tuned to a fifth RFsignal denoted as Rx 134. However, in the 2×2 MIMO mode, if Rx 134 isincident on antenna 130, then a resulting signal is not electricallycoupled 136 with circuitry 129 because RF switch 160 is set toelectrically couple 161 with antenna 120 thereby switching out B5 for Rx134. Furthermore, while in the 2×2 MIMO mode the circuitry 119 iselectrically coupled with antenna 110 and dual RF bands denoted as B3and B4 may both simultaneously Tx 112 and Rx 114 RF signals viaelectrical coupling 116 between circuitry 119 and antenna 110.Therefore, four RF bands (B1-B4) may be active for Tx and Rx in the 2×2MIMO mode and RF signal reception over B5 is blocked because antenna 130is switched out.

1×2 MIMO Mode

Moving now to FIG. 1C, for purposes of explanation, assume mode signal155 is set to the 1×2 MIMO mode. In the 1×2 MIMO mode, RF switch 160electrically couples 163 the antenna 130 with circuitry 129 and dualbandwidth RF communication (B1, B2) using antenna 120 is disabledbecause the antenna 120 is switched out. Here, when antenna 130 has Rx134 incident on it a signal may be electrically communicated (136, 138)to circuitry 129 and that signal may be processed by RF circuitry 150 orother. The processing may be used to determine relative signal strengthbased on the signal, or to make received signal strength indicator(RSSI) measurements based on the signal. Furthermore, while in the 1×2MIMO mode the circuitry 119 is electrically coupled with antenna 110 anddual RF bands (B3, B4) and both bands may simultaneously Tx 112 and Rx114 RF signals via electrical coupling 116 between circuitry 119 andantenna 110. Therefore, two RF bands (B3-B4) may be active for Tx and Rxin the 1×2 MIMO mode in RF chain 152 and RF signals may be received onlyin RF chain 151 via antenna 130. Tx and Rx over B1 and B2 is blocked inthe 1×2 MIMO mode because antenna 120 is switched out.

FIG. 1D depicts a more detailed block diagram 100 d of one example of RF100. In RF chain 151, circuitry 129 may include a band pass filter (BPF)191 coupled (125, 195 a) with the RF circuitry 150 and a diplexer 195.Diplexer 195 may be electrically coupled 160 a with an output of RFswitch 160. A matching circuit 193 may be electrically coupled (120 a,120 b) with antenna 120 and an input to RF switch 160. At least aportion of antenna 130 may be exposed (Exp) (see FIGS. 4A-4E) tofacilitate near field detection of external RF transmitting devices(e.g., a smartphone, tablet, or pad). Additional circuitry may includean electrostatic discharge (ESD) protection circuit 190, a matchingcircuit 192, and an attenuator 194 electrically coupled (130 d, 130 c,130 b, and 130 a) between the antenna 130 and RF switch 160. In RF chain152, BPF's 181 and 183 may be electrically coupled (115, 117, 180 a, and180 b) between a diplexer 185 and RF circuitry 150, and a matchingcircuit 187 may be electrically coupled (110 a, 110 b) between thediplexer 185 and antenna 110.

In FIG. 1E, setting the mode signal to the 2×2 MIMO mode is operative togenerate a signal on 153 that causes RF switch 160 to deselect antenna130 for B5 (e.g., Rx on B5 is switched out) as denoted by a dashed linefor input 130 d to RF switch 160, and to select antenna 120 as denotedby a solid line for input 120 b. Therefore, in the 2×2 MIMO mode, B5 isblocked and B1, B2, B3 and B4 are all available for Tx/Rx in RF chains151 and 152.

In FIG. 1F, setting the mode signal to the 1×2 MIMO mode is operative togenerate a signal on 153 that causes RF switch 160 to deselect antenna120 thereby switching out Tx/Rx on B1 and B2 as denoted by a dashed linefor input 120 b to RF switch 160. Antenna 120 is selected as denoted bya solid line for input 130 d to RF switch 160. Therefore, in the 2×2MIMO mode, B5 is available for Rx only, B1 and B2 are blocked for bothTx and Rx, and B3 and B4 in RF chain 152 are both available for Tx andRx.

FIG. 2 depicts an exemplary computer system 200 suitable for use in thesystems, methods, and apparatus described herein. In some examples,computer system 200 may be used to implement circuitry, computerprograms, applications (e.g., APP's), configurations (e.g., CFG's),methods, processes, or other hardware and/or software to perform theabove-described techniques. Computer system 200 includes a bus 202 orother communication mechanism for communicating information, whichinterconnects subsystems and devices, such as one or more processors204, system memory 206 (e.g., RAM, SRAM, DRAM, Flash), storage device208 (e.g., Flash, ROM), disk drive 210 (e.g., magnetic, optical, solidstate), communication interface 212 (e.g., modem, Ethernet, WiFi),display 214 (e.g., CRT, LCD, touch screen), one or more input devices216 (e.g., keyboard, stylus, touch screen display), cursor control 218(e.g., mouse, trackball, stylus), one or more peripherals 240. Some ofthe elements depicted in computer system 200 may be optional, such aselements 214-218 and 240, for example and computer system 200 need notinclude all of the elements depicted.

According to some examples, computer system 200 performs specificoperations by processor 204 executing one or more sequences of one ormore instructions stored in system memory 206. Such instructions may beread into system memory 206 from another non-transitory computerreadable medium, such as storage device 208 or disk drive 210 (e.g., aHD or SSD). In some examples, circuitry may be used in place of or incombination with software instructions for implementation. The term“non-transitory computer readable medium” refers to any tangible mediumthat participates in providing instructions to processor 204 forexecution. Such a medium may take many forms, including but not limitedto, non-volatile media and volatile media. Non-volatile media includes,for example, optical, magnetic, or solid state disks, such as disk drive210. Volatile media includes dynamic memory, such as system memory 206.Common forms of non-transitory computer readable media includes, forexample, floppy disk, flexible disk, hard disk, SSD, magnetic tape, anyother magnetic medium, CD-ROM, DVD-ROM, Blu-Ray ROM, USB thumb drive, SDCard, any other optical medium, punch cards, paper tape, any otherphysical medium with patterns of holes, RAM, PROM, EPROM, FLASH-EPROM,any other memory chip or cartridge, or any other medium from which acomputer may read.

Instructions may further be transmitted or received using a transmissionmedium. The term “transmission medium” may include any tangible orintangible medium that is capable of storing, encoding or carryinginstructions for execution by the machine, and includes digital oranalog communications signals or other intangible medium to facilitatecommunication of such instructions. Transmission media includes coaxialcables, copper wire, and fiber optics, including wires that comprise bus202 for transmitting a computer data signal. In some examples, executionof the sequences of instructions may be performed by a single computersystem 200. According to some examples, two or more computer systems 200coupled by communication link 220 (e.g., LAN, Ethernet, PSTN, orwireless network) may perform the sequence of instructions incoordination with one another. Computer system 200 may transmit andreceive messages, data, and instructions, including programs, (i.e.,application code), through communication link 220 and communicationinterface 212. Received program code may be executed by processor 204 asit is received, and/or stored in a drive unit 210 (e.g., a SSD or HD) orother non-volatile storage for later execution. Computer system 200 mayoptionally include one or more wireless systems 213 in communicationwith the communication interface 212 and coupled (215, 223) with one ormore antennas (217, 225) for receiving and/or transmitting RF signals(221, 227), such as from a WiFi network, BT radio, or other wirelessnetwork and/or wireless devices, for example. Examples of wirelessdevices include but are not limited to: a data capable strap band,wristband, wristwatch, digital watch, or wireless activity monitoringand reporting device; a smartphone; cellular phone; tablet; tabletcomputer; pad device (e.g., an iPad); touch screen device; touch screencomputer; laptop computer; personal computer; server; personal digitalassistant (PDA); portable gaming device; a mobile electronic device; anda wireless media device, just to name a few. Computer system 200 in partor whole may be used to implement one or more systems, devices, ormethods using the antenna and passive slits as described herein. Forexample, a radio (e.g., a RF receiver) in wireless system(s) 213 may beelectrically coupled 231 with an edge of the antenna. Computer system200 in part or whole may be used to implement a remote server or othercompute engine in communication with systems, devices, or method usingthe antenna and passive slits as described herein. RF 100 may beincluded in the wireless system(s) 213.

FIG. 3 depicts a flow diagram 300 of one example a method formulti-channel dual band wireless communication and wireless near fieldproximity detection. At a stage 301 a state of a MIMO mode signal (e.g.,mode 153) is set to a 1×2 MIMO mode or a 2×2 MIMO mode. An externalsignal may be used to set and/or toggle a state of the MIMO mode signal.As one example, a user pressing or otherwise actuating a switch, button,capacitive switch, touch screen, or other device may trigger thegeneration and/or toggling of the MIMO mode signal. At a stage 303 adetermination may be made as to whether or not the MIMO mode signal isset to a 1×2 MIMO mode. If the state of the MIMO mode signal is set tothe 1×2 MIMO mode, then a YES branch is taken to a stage 305 where theRF chain 151 couples the antenna 130 for Rx only on B5 and RF chain 152couples antenna 110 for both Tx and Rx on B3 and B4. At a stage 311 adetermination may be made as to whether or not the MIMO mode signal haschanged since being set to the 1×2 MIMO mode. If the MIMO mode signalhas not changed, then a NO branch may be taken and flow 300 may end. Ifthe MIMO mode signal has changed, then a YES branch may return flow backto a prior stage, such as the stage 303, for example.

Back at the stage 303, if the 1×2 MIMO mode has not been set, then a NObranch may be taken to a stage 307 where a determination may be made asto whether or not the MIMO mode signal is set to a 2×2 MIMO mode. If thestate of the MIMO mode signal is set to the 2×2 MIMO mode, then a YESbranch is taken to a stage 309 where the RF chain 151 couples antenna120 for Tx and Rx on B1 and B2, antenna 130 is decoupled so that Rx onB5 is blocked, and RF chain 152 couples antenna 110 for both Tx and Rxon B3 and B4. If the 2×2 MIMO mode is not set, then a NO branch may betaken and the flow 300 may return to a prior stage, such as the stage301, for example. At the stage 311, the flow 300 may end if there is nochange in the MIMO mode signal or may flow back to a prior stage, suchas the stage 303, for example.

Table 1 below lists examples of which bands (B1-B5) may Tx or Rxdepending on the state of the MIMO mode signal.

TABLE 1 Band 2X2 MIMO Mode 1X2 MIMO Mode B1 Tx and Rx on 120 NO Tx or Rxon 120 B2 Tx and Rx on 120 NO Tx or Rx on 120 B3 Tx and Rx on 110 Tx andRx on 110 B4 Tx and Rx on 110 Tx and Rx on 110 B5 NO Rx on 130 Rx onlyon 130

Table 2 below lists examples of frequencies for bands (B1-B5) dependingon the state of the MIMO mode signal.

TABLE 2 Band 2X2 MIMO Mode 1X2 MIMO Mode B1 2.4 GHz WiFi on 120 NO Tx orRx on 120 B2 5 GHz WiFi on 120 NO Tx or Rx on 120 B3 2.4 GHz WiFi on 1102.4 GHz WiFi on 110 B4 5 GHz WiFi on 110 5 GHz WiFi on 110 B1 BT on 120NO Tx or Rx on 120 B2 5 GHz WiFi on 120 NO Tx or Rx on 120 B3 BT on 110BT on 110 B4 5 GHz WiFi on 110 5 GHz WiFi on 110 B5 NO Rx on 130 Rx**only on 130

Although Table 2 lists both B1 and B3 as being enabled for Bluetooth Txand Rx, as was stated above, in some configurations, both B1 and B3 mayTx and Rx using Bluetooth, and in other configurations only B1 or B3 mayTx and Rx using Bluetooth. In some configurations B1, B3, or both mayswitch between Tx and Rx on 2.4 GHz WiFi to Tx and Rx on Bluetooth asneeded. For example, in 2×2 MIMO mode, B1 may initially Tx and Rx over120 using 2.4 GHz WiFi and then switch to Tx and Rx on Bluetooth when aBT enabled device is paired with or otherwise establishes a BTcommunications link with RF 100. While B1 continues to Tx and Rx onBluetooth in the 2×2 MIMO mode, B3 may service the Tx and Rx 2.4 GHzWiFi traffic until B1 again becomes available for 2.4 GHz WiFicommunications. The “**” in the column for 1×2 MIMO mode for B5 denotesthat antenna 130 may be detuned for optimal performance at somefrequency that is lower than those for (B1-B4) as described above.

Antenna Using Passive Slits

FIG. 4A depicts a top plan view 490 a of a substrate of an electricallyconductive material 450 in which a plurality of separate apertures(e.g., holes or openings) are formed. Here, those separate apertures aredepicted looking down on a surface 451 of the substrate 450. Therefore,the separate apertures may be described as through holes formed in thesubstrate 450 and extending all the way through the substrate 450 aswill be described in greater detail in FIG. 4B.

One or more of the separate apertures comprises an antenna 130 having alength dimension L that is substantially larger that a width dimensionH. For example, if antenna 130 has the shape of a rectangle as depictedin FIG. 4A, then H is much less than L (e.g., H<<L), such that if L is150 mm then H may be 10 mm or less (e.g., H=3.5 mm). Actual shapes anddimensions of the antenna 130 may be application dependent and are notlimited to the configuration depicted in FIG. 4A or in any other figuresherein. One edge 410 of antenna 130 is electrically coupled with a radiofrequency (RF) system (e.g., RF 100) and an opposite edge 412 iselectrically coupled with a ground potential (not shown) (e.g., aground—GND or chassis ground). Edges 410 and 412 are along a lengthdimension of the antenna 130. As one example, a node 411 on edge 410 maybe electrically coupled with the RF system and another node 413 on theopposite edge 412 may be electrically coupled with the ground potential.In some examples, the electrical connections for nodes 411 and 413 maybe reversed and node 413 electrically coupled with the RF system andnode 411 electrical coupled with the ground potential. Although theposition of the electrical connections to the edges 410 and 412 aredepicted directly opposite each other, that is node 411 is directlyopposite node 413, the nodes may be positioned along their respectiveedges at other locations and the configuration depicted is anon-limiting example. Although one antenna 130 is depicted there may bea plurality of antennas as denoted by 421.

Substrate 450 also includes one or more apertures that define a passiveslit denoted as 401 and 403. Although two passive slits (401, 403) aredepicted there may be just a single passive slit or more than twopassive slits as denoted by 423. Moreover, the relative position on thesubstrate 450 of the passive slit(s) and the antenna(s) are not limitedto the configurations depicted in FIG. 4A or in other figures herein andthe actual size, shape, dimensions, and positions of the passive slit(s)and/or antenna(s) may be application dependent. Passive slits (401, 403)are not electrically coupled with circuitry, the ground potential, orthe RF system. Passive slits (401, 403) are passive structures formed inthe substrate 450 and may operate to modify current flow along substrate450 generated by interaction of an external RF signal (e.g., Rx 134)with antenna 130 as will be described below. Passive slits (401, 403)are not driven by circuitry nor do they generate a signal that iscoupled with circuitry (e.g., circuitry in RF 100).

Typically, dimensions of the passive slits (401, 403) may be much lessthan similar dimensions of the antenna 130. For example, if the passiveslits (401, 403) are rectangular in shape as depicted in FIG. 4A, then awidth dimension W of passive slits (401, 403) may be less than the widthdimension H of the antenna 130. For example, if H is 5 mm, then W may be1.5 mm. Moreover, if the length L of the antenna 130 is 150 mm thenlength D may be 53 mm for the passive slits (401, 403). Passive slits(401, 403) may be placed at various positions along surface 451 ofsubstrate 450, such as opposite ends of antenna 130, for example. Inthat the plurality of apertures are spatially separate from one another,passive slits (401, 403) may be spaced apart from antenna 130 by adistance S that may be the same or different for each passive slit (401,403).

In that the antenna 130 and passive slits (401, 403) are aperturesformed in substrate 450, a void in the opening defined by the apertures,denoted as 402 a for the antenna 130 and 402 b for the passive slits(401, 403), may be occupied by air or some other electricallynon-conductive material, medium, dielectric material, or composition ofmatter. Examples of suitable materials includes but is not limited torubber, plastics, glass, wood, stone, a gas, paper, inert organic orinorganic materials, cloth, leather, a liquid, Teflon, PVDF, minerals,just to name a few. A material that occupies the void/opening may beselected for a functional purpose, an esthetic purpose, or both. In someapplications a functional element such as a switch, button, actuator,indicator (e.g., a LED), microphone, transducer, or the like may bepositioned in void/opening (402 a, 402 b). In other applications thematerial disposed in the void/opening (402 a, 402 b) may include a logo,a trademark, a service mark, ASCII characters, graphics, patterns, oneor more esthetic features, instructions, or the like.

Moving on to FIG. 4B, a cross-sectional view 490 b of the substrate 450depicts in greater detail the void/opening (402 a, 402 b) of theapertures for antenna 130 and passive slits (401, 403). Surfaces 451 and453 of substrate 450 are depicted as being substantially parallel toeach other; however, substrate 450 may have a thickness T that variesand need not be flat, planar, or smooth. Moreover, substrate 450 mayhave a shape including but not limited to an arcuate shape, curvilinearshape, an undulating shape, and a complex shape, just to name a few.Substrate 450 may be made from a perforate material such as a screen,mesh, or other material with perforations formed in it.

Attention is now directed to FIG. 4C where a schematic diagram 190 cdepicts one example of how the opposing sides (410, 412) along thelength L dimension of the antenna 130 may be electrically coupled. Node411 on side 410 is electrically coupled (e.g., 136, 130 d, 463) with aRF 100. The electrical coupling (e.g., 136, 130 d, 463 to RF Switch 160)may be made using a variety of connection techniques including but notlimited to a RF feed, coaxial cable, a wire, a shielded connection, anunshielded connection, a partially shielded connection, an electricallyconductive trace, just to name a few. A node 465 of RF 100 may include atermination device 461, such as a SMA connector or the like, configuredto make an impedance matching termination, such as 50 ohms, for example.Node 413 on side 412 is electrically coupled 471 with a ground potential470. The ground potential 470 may include but is not limited to achassis ground, circuit ground, and power supply ground, just to name afew. The actual selection of the appropriate ground potential may beapplication dependent and is not limited to the ground potentialsdescribed herein. The electrical coupling 471 may use any suitableelectrical connection medium including but not limited to wire, aconductive trace, a cable, and a coaxial cable, just to name a few. RF100 may one or more RF devices including but not limited to RFtransceivers for WiFi, Bluetooth, Ad Hoc WiFi, RF transceivers, RFreceivers, and RF transmitters. RF 100 may include a RF deviceconfigured for and/or devoted to operation with antenna 130 (e.g., a RFreceiver). RF 100 may generate one or more signals on an output 469 inresponse to RF signals received by antenna 130.

In FIG. 4C, an axis X of the antenna 130 is depicted as being orthogonalto an axis Y of the passive slits (401, 403). However, the configurationdepicted is just one non-limiting example and the axis of the antenna130 and passive slits (401, 403), if any, need not have a particularangular orientation. For example, angle α as measured between the X andY axes need not be 90 degrees (e.g., a right angle) and other angularrelationships may be used. Furthermore, any angular relationship betweenaxes of the antenna 130 and the passive slits (401, 403) may vary suchthat a for 403 may be different than a for 401.

Turning now to FIGS. 4D-4E were examples of a live device 477transmitting 134 a RF signal that may be detected by a system (e.g., RF100) using the antenna 130 and passive slits (401, 403) are depicted. InFIGS. 4D-4E, nodes 411 and 413 may be connected as described inreference to FIG. 4C above. Live device 477 is transmitting Tx a RFsignal 134. There may also be other RF sources in an environment inwhich the live device 477 and/or substrate 450 (and its associatedsystem) reside and those RF sources are denoted as transmitting Txsources 461 a-461 n. RF signals from antennas 110 and 120 (e.g., fromB1-B4) may also be present in the environment. For purpose ofdiscussion, a live device is a device that is actively transmitting Tx aRF signal or may be activated (e.g., turned on, controlled or commanded)to transmit Tx a RF signal.

In the cross-sectional view of FIG. 4E, live device 477 is depicted inits most preferred placement, which is directly on the surface 451 ofsubstrate 450. Live device 477 may be positioned at a variety oflocations on surface 451 and the position on surface 451 is not limitedto the position(s) depicted herein. However, in some applications thelive device 477 may be placed above the surface 451 at a distance 480 dthat is in very close near field proximity of the surface 451 of thesubstrate 450 and its associated antenna 130 and passive slits (401,403). Although the received RF signal Rx 134 may be at its strongestwhen the live device 477 is at 480=0 (e.g., directly on surface 451),there may be circumstances where the live device 477 is positioned invery close near field proximity of the surface 451. In the very nearfield region, the power drop off of RF signal strength may be largerthan the well understood 1/R² power drop off rate, and the power dropoff may be 1/R³ or even 1/R⁴. Therefore, even small distances fromsurface 451 may result in a large power drop off in RF signal strengthas received by antenna 130 and detected by RF 100. Distance 480 ispreferably 0.5 meters or less, more preferably 50 mm or less, and evenmore preferably 30 mm or less. Actual distances for very close nearfield proximity will be application dependent and are not limited to theexamples described herein. The live device 477 may comprise a widevariety of wirelessly enabled devices including but not limited to asmartphone, gaming device, tablet or pad, wireless headset or earpiece,a laptop computer, an image capture device, a wireless wristwatch ortimepiece, a data capable strapband or wristband, just to name a few. Insome examples, live device 477 may be positioned in near field proximity(e.g., from about 0.5 meters to about 1 meter) of surface 451 of thesubstrate 450 and its associated antenna 130 and passive slits (401,403). Actual distances for near field proximity will be applicationdependent and are not limited to the examples described herein. Here,near field proximity may be represented by a distance 481 from surface451, where the distance for near field proximity is greater than thedistance for very close near field proximity (e.g., 481>480). Therefore,near field proximity may be regarded as a distance that beginsapproximately were very close near field proximity ends, as denoted bydashed line 482, and extending to an approximate distance denoted bydashed line 483.

In some examples, a user may trigger a mode switch from 2×2 MIMO mode to1×2 MIMO mode by actuating or pressing a button or the like on a chassisor other structure that houses the substrate 450, such as button 488 onsurface 451. Button 488 may be a capacitive touch switch or the like.Button 488 may be positioned at some other location and need not be onsubstrate 450. The user may press button 488 to signal to a device orsystem that includes RF 100 that an attempt will presently be made toposition a live device (e.g., device 477) directly on top of substrate450 or into very close near field proximity of substrate 450. RF switch160 may be signaled 153 to decouple antenna 120 and couple antenna 130(e.g., in 1×2 MIMO mode) in preparation for detecting Rx 134 from thelive device (e.g., device 477). In other examples, an application (APP)or other form of software running on the live device 477 may signal RF100 using one of its radios (e.g., WiFi or BT) that the live device willpresently be positioned directly on or in very close near fieldproximity of substrate 450. A user may activate the APP using a GUI orother interface provide on a touch screen display or the like on thelive device 477 (e.g., a smartphone, tablet, or pad).

In some examples, RF 100 may be configured to switch between 2×2 MIMOmode and 1×2 MIMO mode upon occurrence of some event that may bedetected using antennas 110 and/or 120. For example, RF 100 mayrecognize a RF signature (e.g., via packet sniffing or the like) of apreviously recognized wireless device that is typically placed on thesubstrate 450. RF 100 may upon recognizing the RF signature beginswitching back and forth between 2×2 MIMO mode and 1×2 MIMO mode to seeantenna 130 detects the proximity of the wireless device while the 1×2MIMO mode is active. RF 100 or some other system or device incommunication with RF 100 may take some action upon detection of a livedevice (e.g., device 477) including but not limited to establishing awireless link with the live device, transferring content handling fromthe live device to another device or system, BT pairing with the livedevice, just to name a few.

The systems, wireless media devices, apparatus and methods of theforegoing examples may be embodied and/or implemented at least in partas a machine configured to receive a non-transitory computer-readablemedium storing computer-readable instructions. The instructions may beexecuted by computer-executable components preferably integrated withthe application, server, network, website, web browser,hardware/firmware/software elements of a user computer or electronicdevice, or any suitable combination thereof. Other systems and methodsof the embodiment may be embodied and/or implemented at least in part asa machine configured to receive a non-transitory computer-readablemedium storing computer-readable instructions. The instructions arepreferably executed by computer-executable components preferablyintegrated by computer-executable components preferably integrated withapparatuses and networks of the type described above. The non-transitorycomputer-readable medium may be stored on any suitable computer readablemedia such as RAMs, ROMs, Flash memory, EEPROMs, optical devices (CD,DVD or Blu-Ray), hard drives (HD), solid state drives (SSD), floppydrives, or any suitable device. The computer-executable component maypreferably be a processor but any suitable dedicated hardware device may(alternatively or additionally) execute the instructions.

As a person skilled in the art will recognize from the previous detaileddescription and from the drawing FIGS. and claims set forth below,modifications and changes may be made to the embodiments of the presentapplication without departing from the scope of this present applicationas defined in the following claims.

Although the foregoing examples have been described in some detail forpurposes of clarity of understanding, the above-described inventivetechniques are not limited to the details provided. There are manyalternative ways of implementing the above-described techniques or thepresent application. The disclosed examples are illustrative and notrestrictive.

What is claimed is:
 1. An integrated circuit (IC), comprising: radiofrequency (RF) circuitry configured to implement a 2×2Multiple-Input/Multiple-Output (MIMO) mode and a 1×2 MIMO mode, the RFcircuitry configured to reversibly switch between the 2×2 MIMO mode andthe 1×2 MIMO mode in response to a mode signal electrically coupled witha RF switch, the RF circuitry including a first RF chain electricallycoupled with the RF switch and configured, when the mode signal is setto the 2×2 MIMO mode, to be electrically coupled through the RF switchwith a first dual band antenna and to transmit and receive, using thefirst dual band antenna, first and second dual band RF signals, and thefirst RF chain configured, when the mode signal is set to the 1×2 MIMOmode, to be electrically coupled through the RF switch with a near fieldproximity detection antenna, and to receive only, using the near fieldproximity detection antenna, a fifth RF signal, and a second RF chainelectrically coupled with a second dual band antenna and configured totransmit and receive third and fourth dual band RF signals in the 1×2 or2×2 MIMO modes.